1. Technical Field
The present invention relates generally to a method for restricting overflooding due to address registration of an unstable asynchronous transfer mode (ATM) terminal in an asynchronous transfer mode switch.
2. Related Art
In general, asynchronous transfer mode (ATM) terminals connected to an asynchronous transfer mode switch are automatically assigned their asynchronous transfer mode addresses and register their asynchronous transfer mode addresses in the asynchronous transfer mode switch through an interim local management interface (ILMI) protocol. When the addresses of the asynchronous transfer mode terminals are completely registered in the asynchronous transfer mode switch, other ATM-related protocols such as user network interface (UNI), local area network emulation (LANE or LAN emulation) and private network-to-network interface (PNNI) are interconnected. If an asynchronous transfer mode terminal registers its address in the asynchronous transfer mode switch through the interim local management interface, the private network-to-network interface stores the address in its network topology database for private network-to-network interface routing.
The asynchronous transfer mode terminal repeatedly performs an operation of connecting with the asynchronous transfer mode switch through the interim local management interface to register the address and releasing, when the connection is cut off, the registered address and then reconnecting with the asynchronous transfer mode switch. Therefore, when an unstable asynchronous transfer mode terminal attempts to register its address in the asynchronous transfer mode switch through the interim local management interface, it is necessary to rebuild the private network-to-network interface topology database managed by the asynchronous transfer mode switch, each time the connection is made and cut off. The asynchronous transfer mode switch then regards this as a significant change and performs a synchronization process on every switch belonging to the same peer group through a flooding mechanism.
Such repeatedly performed flooding provides from time to time unstable database information to a network of the corresponding peer group, increasing the unstable factors of the overall network. Therefore, an increase in the network scale and the number of the terminals increases the possibility that unstable terminals will exist.
The present invention has found that overflooding due to address registration of an unstable asynchronous transfer mode terminal in an asynchronous transfer mode switch can be inconvenient and undesirable. Efforts have been made to improve networks in general and asynchronous transfer mode networks in particular.
Exemplars of recent efforts in the art include U.S. Pat. No. 6,028,863 to Sasagawa et al., entitled METHOD AND APPARATUS FOR NEGOTIATING CONNECTION IDENTIFIER, issued on Feb. 22, 2000, U.S. Pat. No. 6,111,881 to Soncodi, entitled SIGNALING PROTOCOL FOR REROUTING ATM CONNECTIONS IN PNNI ENVIRONMENTS, issued on Aug. 29, 2000, U.S. Pat. No. 6,141,322 to Poretsky, entitled METHOD AND APPARATUS FOR PRECEDENCE AND PREEMPTION IN ATM CONNECTION ADMISSION CONTROL, issued on Oct. 31, 2000, U.S. Pat. No. 6,078,586 to Dugan et al., entitled ATM VIRTUAL PRIVATE NETWORKS, issued on Jun. 20, 2000, U.S. Pat. No. 5,872,773 to Katzela et al., entitled VIRTUAL TREES ROUTING PROTOCOL FOR AN ATM-BASED MOBILE NETWORK, issued on Feb. 16, 1999, U.S. Pat. No. 5,963,555 to Takase et al., entitled ROUTER APPARATUS USING ATM SWITCH, issued on Oct. 5, 1999, U.S. Pat. No. 6,002,674 to Takei et al., entitled NETWORK CONTROL SYSTEM WHICH USES TWO TIMERS AND UPDATES ROUTING INFORMATION, issued on Dec. 14, 1999, U.S. Pat. No. 5,854,899 to Callon et al., entitled METHOD AND APPARATUS FOR MANAGING VIRTUAL CIRCUITS AND ROUTING PACKETS IN A NETWORK/SUBNETWORK ENVIRONMENT, issued on Dec. 29, 1998, U.S. Pat. No. 5,831,982 to Hummel, entitled METHOD FOR FORMING ROUTING INFORMATION IN AN ATM COMMUNICATION NETWORK, issued on Nov. 3, 1998, U.S. Pat. No. 5,796,736 to Suzuki, entitled ATM NETWORK TOPOLOGY AUTO DISCOVERY METHOD, issued on Aug. 18, 1998, U.S. Pat. No. 5,831,975 to Chen et al., entitled SYSTEM AND METHOD. FOR HIERARCHICAL MULTICAST ROUTING IN ATM NETWORKS, issued on Nov. 3, 1998, and U.S. Pat. No. 5,761,192 to Hummel, entitled METHOD AND ATM COMMUNICATION NETWORK FOR INTEGRATION OF AN ATM SWITCHING NODE TO BE CONFIGURED INTO AN ATM COMMUNICATION NETWORK, issued on Jun. 2, 1998.
While these recent efforts provide advantages, it is noted that they fail to adequately provide a convenient and efficient method for restricting overflooding due to address registration of an unstable asynchronous transfer mode terminal in an asynchronous transfer mode switch.